1. Technical Field
The invention relates generally to an improved machine vise. More particularly, the invention relates to a machine vise for securing a workpiece adjacent a cutting tool. Specifically, the invention relates to apparatus for positioning an elongated bar-shaped workpiece adjacent a cutting tool such that the workpiece is secured in the vise and rests on an adjustable base to accurately set the length of the workpiece.
2. Background Information
A variety of industries require the fabrication of close tolerance elongated bar-shaped workpieces. Mold-making is one such industry. Specifically, ejector pins and core pins are an integral part of the mold, the manufacture of which requires the mold maker to adhere to close tolerances.
Ejector pins are utilized to remove a recently formed part from the mold. These pins must be held to very close tolerances both in diameter and in overall length. If the pin diameter is even slightly smaller than tolerance, the molded material may be forced between the pin and the mold body decreasing the overall appearance of the part or possibly jamming the mold and reducing cycle time. Alternatively, if the pin diameter is slightly larger than tolerance, the pin will not fit within the pin hole milled into the mold body. If the length of the pin is not held to tolerance, the finished part will not have a smooth surface finish. Moreover, if the pin is to long, when the mold is closed, the pin may cause decreased wall thickness, or may even damage the mold itself.
similarly, core pins must be milled to close tolerances. Core pins are utilized to form or punch holes in the molded product. The diameter and length of these pins must be held within close tolerances for many of the same reasons discussed above with regard to ejector pins.
Whether ejector pins or core pins are being fabricated, it is common for a single mold to require multiple identical pins, or multiple molds to be fabricated simultaneously. The need has arisen for a vise which would allow the pin length to be accurately set for the first pin, with multiple pins being cut to length from this original setup thereby significantly reducing fabrication time and cost.
Further, pins are often nested or cut with various keyways for ease of manufacturing, installation or operation. These keyways and holes must also be manufactured to close tolerances.
While prior art devices are presumably sufficient to achieve the purposes for which they are intended, they present a number of drawbacks. Specifically, known devices do not provide for a means to accurately position an elongated bar-shaped workpiece adjacent a cutting tool such that the workpiece may be both end milled and milled along its longitudinal axis. Further, known vises do not provide a stop block which may be used to set the workpiece length, and which may remain set while subsequent workpieces are milled to length. Further, known machine vises are time consuming to adjust.
Therefore, the need has arisen for a machine vise which will retain a workpiece adjacent a cutting tool, such that the workpiece may be cut to close tolerances whether the part is being end milled, or milled along its longitudinal axis. The need has also arisen for a machine vise wherein multiple pins may be cut to length without resetting the stop block on the vise. Lastly the need exists for a vise which may be quickly adjusted to accept workpieces of varying diameter and length.